cmake,examples: Disable examples until API becomes stable
cmake,examples: Disable examples until API becomes stable

The API will begin rapidly changing now, in an attempt to quickly reach
the stable API that Piglit will use. Until the API becomes stable, disable
the building of examples.

Signed-off-by: Chad Versace <a557f7f75bf28dc19ac99107f5cc7cd6b3fbdb1a@linux.intel.com>

janesma/waffle,janesma/waffle,dcbaker/waffle,yinquan529/waffle-gl-waffle,evelikov/waffle,evelikov/waffle,chadversary/waffle,janesma/waffle,waffle-gl/waffle,fjhenigman/waffle,dcbaker/waffle,fjhenigman/waffle,chadversary/waffle,evelikov/waffle,yinquan529/waffle-gl-waffle,waffle-gl/waffle,maurossi/waffle,maurossi/waffle,chadversary/waffle,dcbaker/waffle,waffle-gl/waffle,waffle-gl/waffle,fjhenigman/waffle,maurossi/waffle,yinquan529/waffle-gl-waffle